Image: Testing the electrical power subsystem of NASA's James Webb Space Telescope

June 6, 2014 by Rob Gutro, NASA

Credit: Northrop Grumman Corporation
(Phys.org) —At Northrop Grumman Aerospace Systems facilities in Redondo Beach, California, integration and test technicians work on a mock-up of the James Webb Space Telescope spacecraft bus, testing the assembly of its parts.

The will provide the necessary support functions for the operation of the Webb Observatory after it is launched into space in 2018.

The bus is the home for six major subsystems:

  • Electrical Power Subsystem
  • Attitude Control Subsystem
  • Communication Subsystem
  • Command and Data Handling Subsystem
  • Propulsion Subsystem
  • Thermal Control Subsystem

The Electrical Power Subsystem or EPS provides the power needed to operate the whole . The EPS converts sunlight shining on the into the needed to operate the other subsystems in the bus as well as the Science Instrument Payload.

The Attitude Control Subsystem senses the orientation of the Observatory, maintains the Observatory in a stable orbit, and provides the coarse pointing of the Observatory to the area in the sky that the Science Instruments want to observe.

The Communication Subsystem is the ears and mouth for the Observatory. The system receives instructions (commands) from the Operations Control Center and sends (transmits) the science and status data to the OCC.

The Command and Data Handling (C&DH) System is the brain of the spacecraft bus. The system has a computer, the Command Telemetry Processor (CTP) that receives commands from the Communications System and directs them to the appropriate recipient. The C&DH also has the memory/data storage device for the Observatory, the Solid State Recorder (SSR). The CTP will control the interaction between the Science Instruments, the SSR and the Communications System

The Propulsion System contains the fuel tanks and the rockets that, when directed by the Attitude Control System, are fired to maintain orbit.

The Thermal Control Subsystem maintains the operating temperature of the spacecraft bus.

Explore further: James Webb Space telescope passes a mission milestone

Related Stories

James Webb Space telescope passes a mission milestone

January 24, 2014

(Phys.org) —NASA's James Webb Space Telescope has passed its first significant mission milestone for 2014—a Spacecraft Critical Design Review (SCDR) that examined the telescope's power, communications and pointing control ...

James Webb telescope team completes optical milestone

January 16, 2013

(Phys.org)—Engineers working on NASA's James Webb Space Telescope met another milestone recently with they completed performance testing on the observatory's aft-optics subsystem at Ball Aerospace & Technologies Corp's ...

NASA's GPM observatory completes first dry run

October 18, 2012

(Phys.org)—NASA's Global Precipitation Measurement (GPM) Core Observatory satellite went through its first complete comprehensive performance test (CPT), beginning on Oct. 4, 2012 at NASA's Goddard Space Flight Center in ...

LADEE closer to exploration of lunar environment

April 10, 2012

NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) has received its integrated propulsion system that will enable the spacecraft to reach the moon. Achieving this milestone means the LADEE observatory is one step ...

Recommended for you

How hot are atoms in the shock wave of an exploding star?

January 21, 2019

A new method to measure the temperature of atoms during the explosive death of a star will help scientists understand the shock wave that occurs as a result of this supernova explosion. An international team of researchers, ...

New eclipsing cataclysmic variable discovered

January 21, 2019

Using the Mobile Astronomical System of Telescope-Robots (MASTER), an international team of astronomers has detected a new eclipsing cataclysmic variable. The newfound object, designated MASTER OT J061451.70–272535.5, is ...

The disintegrating exoplanet K2-22b

January 21, 2019

Exoplanet surveys have yielded many surprises over the years, and the discovery of "disintegrating" exoplanets was one of them. These are planets that produce asymmetric shapes in the dips of the light curves seen as they ...

Total lunar eclipse woos sky watchers

January 21, 2019

An unusual set of celestial circumstances came together over Sunday night and the wee hours of Monday for sky watchers in Europe, Africa and the Americas, where the moon was fully obscured before lighting up again with a ...

Making stars when the universe was half its age

January 18, 2019

The universe is about 13.8 billion years old, and its stars are arguably its most momentous handiwork. Astronomers studying the intricacies of star formation across cosmic time are trying to understand whether stars and the ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.